Jerry,
I can't help you with the head, but I know it would help those who may be able to help if you can determine what engine model is in the tractor. There may be a used head out there for a decent price if the same engine is used in one of the gray market tractors.
What exactly is wrong with the head? Many head problems can be fixed - including welding cracks if the crack is in an accessible location.
Good Luck!